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Vol 8, No 1, January/February 2000
21
Over the past century, 223 million
guns have been introduced into this
country, including 77 million hand-
guns, 66 million shotguns, and 79
million rifles (3 million of the
assault type).
1,2
The presence of a
firearm, now estimated to exist in
half of all US households,
2
increases
an individualÕs risk of killing or
being killed by threefold and of
dying by suicide by fivefold.
3,4
Two thirds of these weapons are
loaded and stored within reach of a
child.
2
This environment results in
150,000 to 500,000 missile injuries
(half involving the extremities)
5
and
40,000 to 50,000 deaths annually.
4-6
Having increased fourfold since the
1950s, the latter figure approxi-

mates the number of Americans
lost during the Vietnam War, is
nearly twice the number of persons
who die of acquired immunodefi-
ciency syndrome each year, and is
three times the number of deaths
associated with drunk driving.
Gunshot wounds, including acci-
dental, intentional, and self-inflicted
injuries, are now the second leading
cause of death and injury for the
youth of this country, especially
African-Americans, killing more
teenage boys than all natural causes
combined.
3,4
The homicide rate for
males aged 15 to 24 in the United
States is roughly 20 times higher
Dr. Bartlett is Assistant Clinical Professor of
Orthopaedic Surgery, University of Vermont
College of Medicine, Burlington. Dr. Helfet is
Director of the Orthopaedic Trauma Service,
The Hospital for Special Surgery, New York.
Dr. Hausman is Chief of The Hand Service,
Mount Sinai Medical Center, New York. Dr.
Strauss is Chief of Trauma, Mount Sinai
Medical Center, New York.
Reprint requests: Dr. Bartlett, University of
Vermont, McClure Musculoskeletal Research

Center, 440 Stafford Hall, Burlington, VT
05405-0084.
Copyright 2000 by the American Academy of
Orthopaedic Surgeons.
Abstract
As a result of the increasing number of weapons in this country, as many as
500,000 missile wounds occur annually, resulting in 50,000 deaths, significant
morbidity, and striking socioeconomic costs. Wounds are generally classified as
low-velocity (less than 2,000 ft/sec) or high-velocity (more than 2,000 ft/sec).
However, these terms can be misleading; more important than velocity is the
efficiency of energy transfer, which is dependent on the physical characteristics
of the projectile, as well as kinetic energy, stability, entrance profile and path
traveled through the body, and the biologic characteristics of the tissues injured.
Although bullets are not sterilized on discharge, most low-velocity gunshot
wounds can be safely treated nonoperatively with local wound care and outpa-
tient management. Typically, associated fractures are treated according to
accepted protocols for each area of injury. Treatment of low-velocity, low-energy
fractures is generally dictated by the osseous injuries, as these are similar in
many regards to closed fractures. Soft tissues play a more critical role in high-
velocity and shotgun fractures, which are essentially open injuries. Aside from
perioperative prophylaxis, antibiotics are probably required only for grossly
contaminated wounds; however, because contamination is not always apparent,
most authors still recommend routine prophylaxis. High-energy injuries and
grossly contaminated wounds mandate aggressive irrigation and debridement,
including a thorough search for foreign material. Open fracture protocols
including external fixation or intramedullary nailing and intravenous antibiot-
ic therapy for 48 to 72 hours should be instituted. If there is vascular damage,
exploration and repair are best performed after prompt fracture stabilization.
Evaluation of the Òfour CsÓÑcolor, consistency, contractility, and capacity to
bleedÑprovides valuable information regarding the viability of muscle. Skin

grafting is preferable when tension is required for wound closure, although
other soft-tissue procedures, such as use of local rotation flaps or free tissue
transfer, may be necessary, especially for shotgun wounds. Distal neurologic
deficit alone is not an indication for exploration, as it often resolves without
surgical intervention.
J Am Acad Orthop Surg 2000;8:21-36
Ballistics and Gunshot Wounds:
Effects on Musculoskeletal Tissues
Craig S. Bartlett, MD, David L. Helfet, MD, Michael R. Hausman, MD, and Elton Strauss, MD
than that in other industrialized
nations.
3
The economic impact of gunshot
trauma is also high. At an inner-
city hospital, annual costs for the
treatment of these injuries can easily
reach $50 million.
3
Nationwide, the
calculated costs of medical treat-
ment, mental health care, emer-
gency transport, police services,
and insurance administration ex-
ceed $2.7 billion annually,
5
most of
which is borne by American tax-
payers.
4,6
These figures do not

include the costs related to addi-
tional loss of productivity, the
attendant pain and suffering, and
the reduced quality of life, estimated
at $63.4 billion each year.
5
For
every gunshot homicide there are
3.3 nonfatal injuries.
3,5
One of these
will be a brain or spinal cord injury,
leading to lifetime expenditures in
excess of $3 million.
3
Because gun-
shot trauma exacts such an enor-
mous toll from both the individual
and society, the surgeon should
take an active interest in both its
prevention and its treatment. An
understanding of ballistics and the
wounding characteristics of various
weapons will also facilitate proper
evaluation and care.
Ballistics
By convention, bullet wounds are
generally classified as low- or high-
velocity injuries. Low-velocity
wounds (Fig. 1) are less severe, are

more common in the civilian popu-
lation, and are typically attributed
to projectiles with muzzle velocities
below 1,000 to 2,000 feet per second
(fps). Tissue damage is usually more
substantial with higher-velocity
(greater than 2,000 to 3,000 fps) mil-
itary and hunting weapons. While
convenient, the terms Òlow-velocityÓ
and Òhigh-velocityÓ can be very
misleading.
7,8
Shotguns, for exam-
ple, are technically low-velocity
weapons, but are responsible for
substantial rates of major soft-tissue,
nerve, vascular, bone, and joint in-
jury,
6,9,10
resulting in a mortality
rate nearly twice that attributable to
other weapons. More appropriate
are the designations Òlow-energyÓ
and Òhigh-energy,Ó which are de-
scriptive of the amount of damage
to the tissues. To appreciate this
distinction, the factors that affect
the transmission of the wounding
capacity of a missile to the tissues
must be considered.

Pulling the trigger of a firearm
releases its firing pin, which strikes
the primer. When crushed, the
primer ignites, producing an in-
tense flame, which enters the main
chamber of the cartridge case and
ignites the powder. The ensuing
generation of a large quantity of
gas and heat (up to 5,200¡F) pro-
duces a pressure as great as 25 tons
per square foot, which ejects the
bullet.
11
Next, the gases trapped in
the bore (the evenly hollowed-out
inner portion of the barrel) expand
and reach a velocity greater than
that of the projectile, further accel-
erating and destabilizing it for a
short distance.
12
The wounding capability of the
bullet is directly related to its ki-
netic energy, determined by the
formula E = M/2 ×V
2
, where E rep-
resents energy; M, mass; and V,
velocity. Before World War II,
bullet and weapon construction

focused on mass, favoring heavier
projectiles of large caliber (diame-
ter of the bullet or rifle bore in
millimeters or as a decimal frac-
tion of an inch). However, in-
creasing mass only produces lin-
ear increases in kinetic energy, but
increasing velocity does so expo-
nentially. In fact, at the speed of
sound (4,760 fps), the rate of ener-
gy conversion into mechanical
disruption of tissue can become
proportional to the third power of
velocity or even higher.
13
There-
fore, over the past five decades,
greater emphasis has been placed
on lighter, spin-stabilized missiles
traveling at high velocities.
The inertia of a projectile acts
through its center of mass, which
lies along its line of flight.
12
Re-
tarding forces act at the center of
pressure, which lies in front of the
center of mass (tip of the bullet) in
a nose-on flight. Any degree of
deviation of the longitudinal axis of

the bullet from its line of flight is
known as yaw, the square of which
proportionally affects its rate of
deceleration.
12
The nonspinning
bullet is inherently unstable and
will have a propensity to tumble.
To best minimize this occurrence
and achieve gyroscopic stability,
Ballistics and Gunshot Wounds
Journal of the American Academy of Orthopaedic Surgeons
22
Figure 1 Anteroposterior (AP) view of
the right humerus of a 29-year-old man
after a small-caliber, low-velocity gunshot
wound with resultant radial nerve neu-
rapraxia. Initial treatment included a coap-
tation splint and discharge home on a regi-
men of oral antibiotics. At 3 weeks, the
plaster splint was replaced by a Sarmiento
brace, in which uneventful healing was
completed. The nerve palsy slowly re-
solved over the ensuing 4 months.
the bullet should be long, thin, and
spun on its axis by helical grooves
in the bore of the firearm (barrel
rifling).
12-14
The highly complex

action of spin on a yawing bullet
(precession), combined with a sec-
ond complicated motion of higher
frequency and lower amplitude
(nutation), will cause the missile to
rotate in a rosette pattern of mo-
tion, (analogous to a spinning top),
imparting stability.
12
More important than velocity is
the efficiency of energy trans-
fer,
8,10,11,13,14
which is dependent on
six factors: (1) The amount of kinetic
energy possessed by the projectile
at the time of impact, such that the
longer the range (distance from the
target), the lower the velocity at
impact.
13
(2) The stability and
entrance profile of the projectile. At
a yaw of 90 degrees (sideways), max-
imal energy transfer is achieved.
8,14
Yaw tends to decrease over longer
distances,
12
allowing the bullet to

hit its target nose-on; at impact,
however, wobbling and then tum-
bling occur. (3) The caliber, con-
struction, and configuration of the
bullet, which can be by far the most
important factors predicting its
effects.
7,11,13
(4) The distance and
path traveled within the body.
Penetrating (not exiting) missiles
deliver their total contained kinetic
energy; perforating (exiting) mis-
siles transfer significantly less.
11,12
(5) The biologic characteristics of
the tissues impacted.
11,15
(6) The
mechanism of tissue disruption
(e.g., stretching, tearing, crushing).
7
On the basis of the interactions
between these many factors, differ-
ent injury patterns will occur or
even coexist. Inefficient energy
transfer by a high-velocity bullet
might produce only minimal dam-
age. In contrast, complete release
of energy by a low-velocity projec-

tile can inflict devastating wounds.
Thus, Cooper and Ryan
14
have
warned that one should Òtreat the
wound [and] not the weapon.Ó
Weapons and Ammunition
Although handguns are typically
low-energy weapons, with muzzle
velocities below 1,400 fps,
11,13
they
are still the most frequently used
firearms in fatal injuries.
1,5
Exam-
ples include the .38-caliber revolver
(600 to 870 fps), the 9-mm pistol,
and the .45-caliber semiautomatic
weapon (860 fps). A small-caliber
short-barreled type, common in
urban areas and costing less than
$50, is the ÒSaturday Night Special.Ó
Named for their rifled barrel,
rifles include low-velocity types,
such as the rarely fatal air rifle
11,13
and the .22 (1,100 to 1,255 fps).
11,13
Higher-velocity military (assault)

rifles include the M-16 (3,250 fps)
11
and the AK-47 (2,340 fps).
7
Even at
300 yd, bullets fired from these par-
ticular weapons retain nearly half of
their original muzzle velocity.
Although the M-16 round has ap-
proximately the same caliber and
weight as the .22, it is fired at a
velocity three times greater than that
of the latter, producing nearly ten
times the amount of kinetic energy
(Fig. 2). Assault rifles have been
involved in 16% of homicides in
New York City but fewer than 2% of
homicides in more rural areas.
1
More common in rural areas,
shotguns fire a Òmissile,Ó consisting
of a few to hundreds of lead pellets,
at a velocity of 1,000 to 1,500 fps.
13
Because of its high efficacy of energy
transfer at close-range, the shotgun
is the most formidable and destruc-
tive of all small arms. A sawed-off
shotgun offers the advantage of
concealment and more rapid dis-

persion of pellets, increasing the
probability of striking the target.
6,13
Damage is based on the choke,
load, barrel length (federal law
requires a minimum of 18 inches),
smooth bore, wadding, powder
charge, and range.
6,16
The choke is
a partial constriction of the bore at
the muzzle that condenses and con-
trols the shot pattern. The tighter
the choke, the smaller the spread of
pellets and the greater the length of
the shot column. ÒGauge,Ó which
refers to the number of lead balls of
the given bore diameter that are
required to weigh 1 lb, is an archaic
term.
11
The load is composed of
different sizes of shot, packed into
what is usually a plastic shell. The
role of wadding is to fill up dead
space in the shell, protect the pow-
der and shot, and seal the bore dur-
ing firing to keep gas behind the
pellets.
11

It is commercially pro-
duced from paper, cardboard, felt,
plastic, or composite materials.
The quantity and type of gun-
powder affect the initial kinetic ener-
gy of the bullet. Gunpowder (black
powder) was originally composed of
a mixture of saltpeter (potassium
nitrate), charcoal, and sulfur and
was measured in drams. Modern
smokeless powder, invented in 1884
and modified much since then, is
measured in dram-equivalents.
11,16
Craig S. Bartlett, MD, et al
Vol 8, No 1, January/February 2000
23
Figure 2 AP view of the right distal
femur of an 18-year-old woman with a
high-velocity M-16 rifle wound. Note the
Òlead snowstormÓ pattern and severe com-
minution. The arteriogram revealed no
gross arterial damage.
Bullets are composed primarily
of lead combined with varying
amounts of other metals depend-
ing on their desired final hardness
(0.5% antimony, 0.3% copper, and
0.05% other metals in one common
formulation).

17
They can be modi-
fied in many ways to improve
energy transference, including full
or partial (soft-point) metal jacket-
ing, partial metal jacketing with a
cavity at the tip (hollow point),
controlling expansion with use of
aluminum, scoring, bonding, com-
bining multiple projectiles into
one cartridge, and adding an
explosive charge.
7,11,14,18
The com-
mon failure of explosive bullets to
detonate on impact presents con-
tinuing danger to both medical
personnel and patients. Magnum
shells and cartridges contain a
heavier than standard powder
charge, which increases projectile
energy by 20% to 60%.
6
Scoring
the bullet (e.g., the dumdum)
makes it more likely to fragment
when subjected to strong in-flight
physical forces.
13,18
A bullet com-

posed of bonded fragments of iron
or lead (e.g., .22-caliber frangible)
will disintegrate on striking a hard
surface.
Fully jacketed bullets are uti-
lized primarily in assault rifles.
These have a lead or steel core,
which is covered by an outer jacket
of cupronickel or gilding metal
(copper or zinc) to minimize defor-
mation. Therefore, they invariably
exit the victim if he is the primary
target within a few hundred yards
of the muzzle. In contrast, both
soft-nose and hollow-point bullets
flatten out on impact, the latter
expanding up to twice their origi-
nal diameter and quadrupling the
amount of tissue struck.
7
At high
velocities, these bullets also shed as
they travel through the body, creat-
ing a characteristic radiographic
Òlead splatterÓ or Òlead snowstormÓ
pattern
11
(Fig. 2). Most hunting
bullets also exit the body.
11

Shot shells are handgun car-
tridges with bird shot encased in
plastic. The plastic contains the
shot until impact, often producing
fatal results at distances of less than
10 ft.
11,18
In contrast, a shotgun slug
(a single large projectile mounted
into a shotgun shell) can produce
massive internal injuries compara-
ble in severity to those of high-
velocity rifle bullets.
The Bullet Wound
An impact velocity of only 150 to
170 fps is required to penetrate
skin.
6,12
Most entrance wounds,
regardless of range, are oval to cir-
cular with a punched-out clean
appearance and are often sur-
rounded by a zone of reddish dam-
aged skin (the abrasion ring).
11
While powder tattooing of the skin
implies a close-range wound, the
fact that there are different forms of
propellant powder makes this an
unreliable finding. Also indicative

of a close-range injury is a cherry-
hue appearance of underlying
muscle due to carboxyhemoglobin,
formed by carbon monoxide re-
lease during combustion.
11
Damage is created by several
mechanisms, including the actual
passage of the missile through tis-
sue, a secondary shock wave, and
cavitation. On striking its target,
the bullet creates a temporary cavi-
ty at the entry site due to stretching
forces and the vacuum created by
its passing. The volume of this cav-
ity is proportional to the energy
transferred by the missile (Fig. 3)
12
;
a maximum size of 10 to 40 times
the diameter of the bullet is reached
in 1 to 4 msec,
11,13,19,20
with internal
pressures reaching 100 to 200 atm.
20
This violent event in high-velocity
injuries over 2,500 fps can create
damage of an almost explosive
nature.

12
During the 10- to 30-msec life-
time of the temporary cavity,
20
its
vacuum may pull foreign material
into the wound.
12,13
However, most
bullets are pointed and transfer little
from the entry site.
14
A Òtail splashÓ
or Òsplash backÓ effect at high velo-
cities can cause backward hurling of
injured tissue.
8,11,20
After the bullet
passes, the temporary cavity col-
lapses and re-forms repeatedly with
diminishing amplitude, leaving a
smaller permanent cavity.
13,20
The
more the elastic capacity of the sur-
rounding tissue has been exceeded,
the greater the size of this perma-
nent cavity.
Wang et al
15

separate the wound
area into three zones: (1) a primary
wound track (the permanent cavi-
ty); (2) a contusion zone of muscle
adjacent to the track; and (3) a con-
cussion zone (variable outside con-
gestion). In uncomplicated low-
velocity civilian gunshot wounds,
this area is essentially only a few
cells deep.
21
Therefore, these
wounds rarely require full explo-
ration.
22
However, the volume of
devitalized muscle grows with
increasing energy, becoming visual-
ly apparent at velocities over 1,000
fps and resulting in extensive bruis-
ing at velocities over 2,000 fps.
8,12
After impact by a high-velocity,
rapidly decelerating, deforming,
and disintegrating projectile, tissue
destruction may extend up to sever-
al centimeters radially from the
track.
13
Fascial planes may serve as

channels for the dissipation of
explosive force, leading to signifi-
cant remote tissue damage.
14
As a
result, disruption of muscle capil-
lary blood supply, rupture of gas-
containing viscera, and fractures
can occur even without a direct im-
pact.
11,12
Energy loss by the bullet and tis-
sue disruption along the wound
track are not uniform, due to varia-
tions in tissue density and the
behavior of the bullet as it travels
from one structure to another.
15
Soft, bulky, homogeneous solid
organs, such as liver, spleen, and
Ballistics and Gunshot Wounds
Journal of the American Academy of Orthopaedic Surgeons
24
muscle (specific gravities of 1.01 to
1.04), are violently disrupted when
transferred kinetic energy exceeds
the elastic limits of the tissue.
13,20
Histologically, swelling of muscle
fibers to as much as five times nor-

mal size can be observed, with clot-
ting of muscle cytoplasm, loss of
striations, and interstitial extravasa-
tion of blood. Lactate levels increase
to as much as six times normal, and
depletion of adenosine triphosphate,
creatine phosphate, and glycogen
occurs.
23
These changes result in
local edema, which may lead to a
compartment syndrome, further in-
creasing the insult to the soft
tissues.
7
Bone (specific gravity of 1.11) can
be shattered beyond recognition, but
less dense and more elastic tissues,
such as skin and lung (with much
lower specific gravities of 0.2 to 0.5),
may be virtually unscathed.
11,14,20
Although capillaries are prone to
rupture, larger arteries (unless
directly struck) are remarkably resis-
tant to injury.
12
Likewise, larger
nerve trunks, while susceptible to
neurapraxic lesions, are rarely com-

pletely disrupted.
12
Exit wounds can appear stellate,
slitlike, crescentic, circular, or com-
pletely irregular.
11
With greater
velocities, bullet deformation, and
tumbling within the body, these
typically become larger and more
irregular than entrance wounds.
13
For example, a full-metal-jacket
bullet will produce a small cylin-
drical cavity until it begins to tum-
ble. When this occurs, massive
amounts of kinetic energy are re-
leased, widening the cavity and
exit wound. However, a retro-
grade effect can occur if the bullet
slows and releases a large amount
of energy immediately after impact
(as may occur with rapidly expand-
ing hunting ammunition). This
will form a track with a cone based
at the entry site.
11,13
Thus, contrary
to popular opinion, an exit wound
is not necessarily larger than the

corresponding entrance wound. In
contrast to entrance wounds, cavity
formation at the exit site may allow
substantial quantities of material to
be sucked into the wound, particu-
larly when the velocity exceeds
2,000 fps.
11
The Shotgun Wound
Complicated formulas exist to de-
termine the range of a shotgun
wound. However, it may be easily
estimated by measuring the diame-
ter of the spread on the patient. As
the shot pellets travel from 2 to 100
yd, they separate slightly less than
1 in/yd.
6,16
Soft-tissue shotgun injuries can
be graded from the most extreme
(type III) to benign (type 0)
6
(Fig. 4).
Type III (Òpoint blankÓ) wounds are
due to impact from a range of less
than 3 yd and are extensive, with
the concentrated cloud of shot
potentially destroying everything in
its path. Wound diameters of 6 in
or less often herald injury to deeper

structures.
16
The presence of soot is
evidence of a blast from a range of 1
ft or less.
11
Massive soft-tissue
destruction and bacterial contami-
nation from wadding require ag-
gressive treatment and often long
hospital stays. Type II (close-range)
wounds, due to impact from a
range of 9 to 21 ft, are almost as
severe and penetrate deep to the
fascia. These are less likely to have
embedded wadding, which tends to
fall away after distances greater
than 6 ft.
6,11
Type II and III wounds are asso-
ciated with high rates of commin-
uted fractures (32% to 48%), major
soft-tissue disruption (43% to 59%),
vascular injury (23% to 35%), and
peripheral nerve damage (21% to
58%).
9,10,24
Furthermore, vascular
Craig S. Bartlett, MD, et al
Vol 8, No 1, January/February 2000

25
A
B
Figure 3 Blocks of gelatin perforated by .30-caliber missiles at less than 1,000 fps (A) and
at 2,800 fps (B). Arrows indicate missile tracks. (Reproduced with permission from
Ziperman HH: The management of soft tissue missile wounds in war and peace. J Trauma
1961;1:361-367.)
and neural injuries frequently coexist,
and multiple injuries are often pres-
ent. Such global trauma leads to
amputation rates as great as 20% to
50%
10,24
and high mortality rates.
In injuries from distances greater
than 7 yd, a large cloud composed
of widely scattered missiles pro-
duces many small holes but rarely
major soft-tissue disruption.
6
Such
injuries can often be treated simply
as multiple low-velocity wounds
6
and are grouped as type I (long-
range), which penetrate to the sub-
cutaneous tissues and deep fascia,
and type 0, which involve only skin
penetration. Beyond 20 to 50 yd
(maximal range), the rapidly decel-

erating and poorly shaped (aerody-
namically) spherical pellets create
negligible damage.
13
Bone Involvement
Bone is a specialized form of dense
connective tissue composed of cal-
cium salts embedded in a matrix of
collagenous fibers, which is rarely
damaged without concomitant
muscle injury. A minimum velocity
of 195 to 200 fps is necessary for a
bullet to breach its cortex.
6,20
The
clinical and radiographic appear-
ance of the entrance hole is usually
a punched-out round to oval shape
with a sharp beveled edge. In con-
trast, the exit site typically has an
excavated, conelike appearance
with a variable amount of com-
minution.
11
Generally, the greater
the velocity of the missile, and
therefore the greater its contained
kinetic energy, the greater the com-
minution at both entry and exit
sites (Fig. 2).

Lower-velocity projectiles can
produce many different fracture
patterns, either incomplete or com-
plete. There are three types of
incomplete fractures
13,25
: (1) the
Òdrill-holeÓ fracture, which usually
occurs through the soft metaphy-
seal region of long tubular bones,
and is characterized by entrance
and exit holes with diameters close
to the diameter of the bullet; (2) the
unicortical (ÒdivotÓ) fracture,
which involves a portion of bone
removed from the main structure
and occasionally a nondisplaced
fracture line extending from the
divot; and (3) the chip fracture,
more common in stab wounds and
rarely seen after bullet injuries.
Complete fractures are more fre-
quent in diaphyseal bone and in-
clude patterns such as the single
and double ÒbutterflyÓ fractures.
Their spectrum ranges from frac-
tures secondary to indirect forces to
highly comminuted patterns. On
impact, bone fragments are pro-
pelled toward the periphery of the

temporary cavity. Although these
can become secondary missiles,
causing damage to more distant
structures, more commonly they
quickly retract to the parent bone.
11
Frequently, other secondary mis-
siles include articles of clothing,
such as buttons and belt buckles.
13
Physeal damage has been noted
in 16% of skeletally immature
patients who sustain a gunshot
wound.
26
This is usually due to di-
rect damage as the bullet passes
near a growth plate, which is easily
noted on initial radiographs. How-
ever, physeal injury can theoretically
occur remote from the site of the
wound track, leading to unforeseen
growth arrest.
27
Joint Involvement and
Metal Intoxication
A bullet passing through a joint can
damage bone, cartilage, ligaments,
and menisci. Tornetta and Hui
28

noted a 42% incidence of meniscal
injury and a 15% incidence of chon-
dral damage in knee joints violated
by low-velocity projectiles. Articu-
lar damage may be crippling, with
loss of normal anatomic contours
leading to severe posttraumatic
degenerative arthritis. Contamina-
tion by bullet fragments can result
in joint sepsis, rapid chondrolysis,
and joint destruction.
Lead intoxication (plumbism)
can manifest from 2 days to 40
years after a gunshot injury.
29
Its
most common causes include bullet
fragments within a joint space,
bone, or (rarely) intervertebral
disk.
11,22,30
Lead fragments in soft
tissues are quickly covered by
avascular scar tissue,
29
which pre-
vents their migration and perhaps
uptake by the body. However,
intra-articular lead dissolves in
synovial fluid and may be deposit-

ed in subsynovial tissues, leading
to chronic irritation, arthritis, and
(rarely) systemic effects (such as
neurotoxicity, anemia, nausea and
emesis, abdominal colic, and renal
disease). Furthermore, toxicity
Ballistics and Gunshot Wounds
Journal of the American Academy of Orthopaedic Surgeons
26
6 ft
12 ft
24 ft
Figure 4 Diameter of the spread of a shot
column as range increases. Top, Type III
(point-blank) pattern. Center, Type II
(close-range) pattern. Bottom, Type I
(long-range) pattern. (Reprinted with per-
mission from DeMuth WE Jr: The mecha-
nism of shotgun wounds. J Trauma
1971;219-229.)
may rapidly accelerate in the pres-
ence of metabolic disorders, alco-
holism, or acute infection.
13
Two
deaths have been reported.
11
The
use of chelating agents is the initial
treatment for lead intoxication.

Bullet removal is usually neces-
sary.
13,29
Copper, another metal common
in firearm projectiles, is also neuro-
toxic.
17
However, unlike lead, cop-
per causes considerable local soft-
tissue inflammation, necrosis, and
erosion. Nickel can also be inflam-
matory. Zinc and aluminum be-
have similarly to lead in the soft
tissues.
17
The Wandering Missile
Vascular embolization by bullets,
shot, or fragments occurs in rare
instances.
11,13,31,32
The .22-caliber
bullet is the most commonly in-
volved projectile. Almost one fifth
of cases involve the neck or upper
extremities.
32
Migration of missiles
into the portal system, pericardial
space, spinal cord, kidneys, ureters,
urethra, and lungs has also been

observed.
6,31
Contamination and
Infection
Contrary to popular belief, bullets are
not sterilized on discharge.
11,12,19,33,34
Furthermore, shotgun wadding has
been associated with a high degree
of wound contamination,
10,34
espe-
cially in the case of older ammuni-
tion, in which the wadding was
often composed of clostridia-laden
cattle hair and jute, and modern
Òhome loadsÓ created with a variety
of substances. Additional sources of
infection include clothing frag-
ments, skin flora, and other contam-
inants. Therefore, primary closure
is contraindicated. Injuries to the
abdomen or bony pelvis are of par-
ticular concern, because of their
close association with bowel injury,
which dramatically increases the
risk of sepsis.
30
Nonviable muscle, especially in
an anaerobic environment, is an

ideal pabulum for the growth of
many types of bacteria, especially
clostridia.
12,13
Following a gunshot
wound, the number of aerobes in
devitalized muscle has been
observed to be 10,000 organisms
per gram of tissue at 6 hours and
100,000 at 12 to 24 hours, with the
quantity of anaerobes at 6 hours
falling within this range.
35
There-
fore, debridement is optimally per-
formed within 6 to 8 hours of injury.
However, this timing is inexact due
to the degree of tissue destruction,
the presence of shock, and host re-
sistance.
35
When there is too much devital-
ized tissue to be absorbed or too
great a bacterial load, the body will
attempt to wall off the necrotic
mass with a fibrin barrier and expel
it after approximately 10 days.
7
However, without access to the
outside, this mass will form an

abscess. Incomplete removal of
debris, such as shotgun wadding,
can also result in abscess formation
and chronic drainage. In these
cases, imaging of the abscess with
contrast material may help locate
any foreign material before explo-
ration.
Most gunshot wounds are not
complicated by infection, but infec-
tions by certain pathogens are asso-
ciated with increased morbidity.
Clostridial infection can range from
cellulitis to diffuse myonecrosis
(gas gangrene). It usually develops
over 3 days, but may occur within
6 hours of injury. Less commonly,
streptococcal infection develops
over the course of 3 to 4 days, with
systemic reactions not appearing
until late. Although rare, wound
botulism can occur even in clinical-
ly clean wounds, and should be
suspected in the presence of bulbar
and descending symmetric motor
paralysis.
36
Assessment
In a study of 16,316 patients with
gunshot wounds of the extremities,

Ordog et al
2
noted a 17% overall
incidence of vascular injury based
on positive findings by exploration
and/or arteriography. However,
the presence of a vascular injury is
dependent on the location of the
wound (Table 1), its severity, and
the type of weapon used. Such
details should be considered when
Craig S. Bartlett, MD, et al
Vol 8, No 1, January/February 2000
27
Table 1
Relationship of Wound Location and Incidence of Vascular Injury
*
Location of Wound Incidence of Vascular Injury, %

Lateral thigh <1
Medial or posterior thigh 7-9
Popliteal fossa 9-10
Calf or leg 18-22
Upper arm or shoulder 9-10
Medial or posterior upper arm 6-8
Forearm or antecubital fossa 17-22
* Adapted with permission from Ordog GJ, Balasubramanium S, Wasserberger J, Kram
H, Bishop M, Shoemaker W: Extremity gunshot wounds: Part one. Identification and
treatment of patients at high risk of vascular injury. J Trauma 1994;36:358-368.

Based on correlation with arteriography.
attempting to identify the presence
of a potentially limb- or even life-
threatening condition.
Most vascular injuries after pen-
etrating trauma are manifested by
ÒhardÓ physical findings, which
permit a rapid and accurate diagno-
sis.
2,13,37
These include a pulse
deficit; a cold, lifeless extremity;
cyanosis distal to the wound; a
bruit or thrill; pulsatile or uncon-
trollable bleeding; and a large or
expanding hematoma or pseudo-
aneurysm. A progressive neurologic
deficit may signal the presence of
the latter. ÒSoftÓ signs of a vascular
injury include a history of hemor-
rhage, hypotension, or a static neu-
rologic deficit. Unfortunately, even
after complete arterial disruption, a
weak but palpable pulse might still
be present. Accurate pulse assess-
ment of a traumatized limb with
normal perfusion can be hindered
by edema, a hematoma, dressings,
or splints.
38

Generally, arteriography is ex-
tremely sensitive, quite specific for
identification of vascular injury, and
useful for surgical planning for treat-
ment of complex wounds (Fig. 2).
2,13
It is particularly helpful after shot-
gun injuries, because of the frequent
occult vessel damage.
6
However,
this imaging modality is expensive,
has inherent risks, and is sensitive
enough to detect occult findings that
may resolve spontaneously.
2
Due to
these limitations, arteriography may
ultimately be replaced by noninva-
sive duplex ultrasonography, a
modality just as sensitive but with-
out the associated complications.
2,38
When the physical examination indi-
cates the presence of a well-localized
arterial injury, preoperative arteriog-
raphy is unnecessary.
2,38
In contrast,
the absence of ÒhardÓ findings of

vascular injury warrants a period of
observation.
In addition to appropriate ex-
tremity imaging, it is important to
obtain radiographs one body cavity
above and one body cavity below
any entrance or exit wound.
13
Clothing, most wadding, and even
some metal jackets may be difficult
to see on plain films, making a care-
ful inspection mandatory. Clues
that suggest the presence of a cloth
foreign body include radiographic
evidence of an irregular or spurred
bullet, a relatively large entrance
wound for the estimated caliber and
range, and the absence of a frag-
ment of the patientÕs clothing at the
entrance site.
13
Careful evaluation
is also crucial when any metal frag-
ments lie in proximity to a joint
space. Although the presence of
joint violation or an intracapsular
bullet can usually be determined on
the basis of the fracture pattern, the
plain-radiographic appearance, and
the results of joint aspiration (if nec-

essary), the most sensitive test
remains a fluoroscopically assisted
arthrogram.
39
If this is impractical
or inconclusive, a computed tomo-
graphic scan should be obtained.
There are several important med-
icolegal issues that pertain to evalu-
ation and treatment. Care must be
taken to preserve evidence by cut-
ting aroundÑnot throughÑbullet
holes in the patientÕs clothing. The
location, size, shape, and nature of
both the entrance and exit wounds
must be precisely documented.
Medical teams have often been inat-
tentive on this point, with one study
noting that fewer than 3% of charts
have an adequate description of the
wound.
7
Bullets should be marked
only on the nose or base to preserve
the rifling characteristics, and any
wadding or loose pellets should be
retained for evidentiary purposes.
11
Electrodiagnostic studies in the
early postinjury period cannot dis-

tinguish between a neurapraxic
lesion and transection. Follow-up
studies at 6 weeks and 3 months
can show signs of early recovery,
but their utility is limited.
24,40
The
presence of spontaneous fibrilla-
tions and muscle irritability is a
sign of muscle denervation, indi-
cating axonal disruption. In gener-
al, expectations of these studies
exceed their capabilities.
Conservative Treatment of
Low-Energy Wounds
Most low-velocity gunshot wounds
may be safely treated nonopera-
tively, with simple local wound
care (superficial irrigation and
careful cleaning followed by a
dressing, with or without antibi-
otics) and outpatient management
(Fig. 5).
2,19,33,34,41,42
These Òminor
woundsÓ include low-energy un-
contaminated injuries of skin, sub-
cutaneous tissue, and muscle and
fractures not requiring operative
stabilization. Tetanus prophylaxis

with a reinforcing booster of 0.5
mL of tetanus toxoid is indicated
for all gunshot-wound patients
who are not completely immu-
nized (fewer than three immuniza-
tions) or who have uncertain im-
munization histories.
37,43
Anyone
who has not had an immunization
within 5 years requires a booster.
Those not previously immunized
will also require a minimum of 250
to 500 units of human tetanus im-
mune globulin.
13,37,43
Aside from perioperative prophy-
laxis, antibiotics are probably re-
quired only for grossly contaminated
wounds (Table 2).
19,21,33,34,37,41,42,44-48
Dickey et al
33
reported similar rates
of infection in a prospective random-
ized study of 73 patients treated with
or without antibiotics. However,
because contamination is not always
apparent, most authors still recom-
mend routine prophylaxis.

19,34,41,44,45
Hansraj et al
45
have suggested
treatment for 2 days with an intra-
venous antibiotic, such as cefazolin,
for minor wounds with cortical bone
defects. In their study, substitution
of a long-acting, broad-spectrum
cephalosporin (ceftriaxone) allowed
discharge 1 day earlier than for
patients treated with cefazolin, and
Ballistics and Gunshot Wounds
Journal of the American Academy of Orthopaedic Surgeons
28
Craig S. Bartlett, MD, et al
Vol 8, No 1, January/February 2000
29
No
Signs of vascular injury?
No
Proximate injury
†
? Angiography
‡
Duplex Doppler
Negative
Observe
Exploration*
Positive

NegativePositive
NegativePositive
Exploration*
Angiography
Yes
Yes
No
Yes
Signs of vascular injury?
YesNo
If proximate injury,
†
intraoperative
angiography
Low-energy
wound
Discharge home
(if no other injuries)
High-energy
wound
Exploration or
intraoperative
angiography
Extremity gunshot injury with high-energy wound, severe contamination,
joint penetration, unstable fracture requiring surgical stabilization, or
clinically unstable patient with signs and symptoms of vascular injury?
ABCs of trauma care
Tetanus prophylaxis
Initial local debridement in ED
Cleanse with povidone and normal saline

Sterile dressing
Consider initial dose of cefazolin, 1 g
Splint unstable fracture
Definitive wound and fracture care:
Local debridement in ED
Irrigation of wound
Splint or cast, as fracture dictates
Ciprofloxacin, 750 mg PO bid x 3 days
(alternative: cephalexin or dicloxacillin)
Closure by secondary intention
Definitive wound and fracture care:
Irrigation and local debridement in OR
Arthroscopy or arthrotomy for joint penetration
Stabilize as fracture pattern dictates
Cefazolin, 1 g IV q8h x 48-72 h
Closure by secondary intention
Definitive wound and fracture care:
Irrigation and local debridement in OR
Stabilize as fracture pattern dictates
Cefazolin, 1 g IV q8h x 48-72 h
Closure by secondary intention
Definitive wound and fracture care:
Irrigation and local debridement in OR
Stabilize as fracture pattern dictates
Cefazolin, 1 g IV q8h x 48-72 h
Closure by secondary intention
Aggressive irrigation and debridement in OR
Excise contaminated tissue
Explore wound tract
External fixation common (possibly IM nail, rarely ORIF)

IV antibiotics as per open-fracture protocols
(type I, II, or III), continue at least 48-72 h,
but also until wounds are clean (up to 1-2
weeks for severe contamination)
Repeat surgical debridement q48h until
wounds are clean
Closure by secondary intention (possible
skin graft or flap)
Figure 5 Suggested treatment for gunshot wounds. Abbreviations: bid = twice a day; ED = emergency department; IM = intramuscular;
IV = intravenous; OR = operating room; ORIF = open reduction and internal fixation; PO = by mouth; q8h = every 8 hours, * = guidelines
for exploration: exploration is appropriate unless the injury involves only a single vessel below the trifurcation of the popliteal artery or
distal to the midforearm (such an injury is not generally explored unless there is a diagnosis of compartment syndrome, arteriovenous fis-
tula, or pseudoaneurysm);
†
= proximate injuries are defined as those in which the missile track passes within 1 inch of a known anatomic
path of a major vessel;
‡
= if there are ÒsoftÓ signs of vascular injury, can consider duplex Doppler first.
Ballistics and Gunshot Wounds
Journal of the American Academy of Orthopaedic Surgeons
30
Table 2
Suggested Treatment Regimens for Gunshot Wounds
*
Authors Study Design Wound Type

Antibiotic Regimen
Hansraj et al
45
Prospective Low-velocity with minor fractures Ceftriaxone, 1g IV qd × 2 doses, or

(excludes head, spine, feet) cefazolin, 1g IV q8h × 7 doses
Ordog et al
37
Retrospective Minor (87% low-velocity, 4%-6% Usually cephalosporin or
with fractures) dicloxacillin PO
Geissler et al
41
Prospective Low-velocity with minor fractures Cefonicid, 1g IM × 1, or
cefazolin, 1g q8h × 48 h
Dickey et al
33
Prospective Low-velocity with minor fractures Cefazolin, 1g IV q8h × 24 h
randomized
Woloszyn et al
19
Retrospective Low-velocity fractures (13% IV antibiotics × 3d or cephalexin,
required open reduction and 250-500 mg PO qid × 7-10 d
internal fixation or arthrotomy)
Brettler et al
48
Retrospective Low-velocity (53% with fractures, Cephalothin, 2 g IV initially,
15% requiring emergent surgery) then × 3 d (92% of patients),
or other antibiotics (8%)
Patzakis et al
34
Prospective All gunshot fractures Penicillin/streptomycin or
randomized cephalothin, 100 mg/kg of body
weight in divided doses q6h
IV × 10-14 d
Brien et al

44
Retrospective Low-velocity fractures First-generation cephalosporin plus
aminoglycoside, IV × 72 h
Molinari et al
46
Retrospective Low-velocity fractures Varying short courses of IV
antibiotics
Nowotarski et al
47
Retrospective Low- to medium-velocity fractures Cefazolin, IV × 48 h (average)
Wright et al
21
Retrospective Low-velocity fractures First-generation cephalosporin,
IV × 48 h
Knapp et al
42
Prospective Low-velocity fractures Cephapirin, 2 g q4h plus
randomized gentamicin, 80 mg q8h, or
ciprofloxacin, 750 mg bid × 3 d
* Abbreviations: bid = twice a day; ED = emergency department; IM = intramuscular; IV = intravenous; NS = normal saline;
OR = operating room; PO = by mouth; q8h = every 8 hours; qd = every day; qid = four times a day.

ÒMinorÓ fractures defined as stable fractures that did not require surgical stabilization (i.e., patients underwent closed fracture treatment).
à
Same wound care as would have been performed in ED for wounds with nonoperative fractures.
¤
Some patients counted more than once due to multiple fractures.
¦
Historical control (randomized retrospective).
#

No statistical significance between results for two treatments.
saved an estimated $2,348 for each
patient. Similarly, Geissler et al
41
noted cost savings and a low rate of
infection (4%) for patients treated
with a single intramuscular dose of
cefonicid (compared with 4% for a
48-hour course of an intravenous
antibiotic). In a prospective ran-
domized study, Knapp et al
42
noted
a similar rate of infection (2%) in 120
patients with minor fractures, who
were treated with a 3-day course of
either intravenous cephapirin and
gentamicin or oral ciprofloxacin.
Other studies
19,37
have found that
short courses of cephalexin or di-
cloxacillin may be given for uncom-
plicated injuries and outpatient pro-
phylaxis. At least 24 to 48 hours of
intravenous antibiotic therapy is rec-
ommended after joint penetration,
28
although some authors have advo-
cated a 3-day course of cefazolin and

gentamicin.
39
Ordog et al
37
treated 16,892 of
28,150 patients who sustained low-
velocity gunshot wounds (4% with
minor fractures not requiring oper-
ative stabilization) on an outpatient
basis, applying an antibiotic oint-
ment with each wound dressing.
Infections developed in only 1.8%
of those patients; all responded to
oral antibiotics. This is even more
impressive because only 5% had
received prophylactic antibiotics.
The six pseudoaneurysms that oc-
curred were all successfully treated
with elective surgery. No patient
developed lead toxicity or died as a
result of outpatient management.
A conservative estimate of the cost
savings during this study was $38
million.
Indications for Surgery
The presence of massive tissue
damage, vascular injury, progres-
sive neurologic deficit, obvious
contamination or necrosis, joint or
gastrointestinal tract involvement,

compartment syndrome, or uncer-
Craig S. Bartlett, MD, et al
Vol 8, No 1, January/February 2000
31
Wound Care No. of Patients
¤
Infection Rate
Irrigation with NS in ED 31 (ceftriaxone) 0% (ceftriaxone)
#
28 (cefazolin) 0% (cefazolin)
#
Local care in ED; antibiotic 16,047 (no antibiotics) 1.8% (all patients)
ointment; discharge home 845 (PO antibiotics) 6% (inpatients with
antibiotic prophylaxis)
Local wound care with 25 (IM antibiotics) 4% (IM antibiotics)
#
3 L of 10% povidone-NS 25 (IV antibiotics)
¦
4% (IV antibiotics)
#
in ED; discharge home
Local wound care with 36 (antibiotics) 2.8% (antibiotics)
#
H
2
O
2
in ED 37 (no antibiotics) 2.7% (no antibiotics)
#
Local wound care with 3 L of 80 (IV antibiotics) 0% (IV antibiotics)

#
10% povidone-NS; excise 52 (PO antibiotics) 3.8% (PO antibiotics)
#
1 mm from wound edge
in ED; discharge home (87%)
Local wound care with 2 L 136 (antibiotics) 0.7% (antibiotics)
of 25% povidone-NS in 12 (no antibiotics) 8.3% (no antibiotics)
ED (85%)
Povidone-NS in ED; 27 (no antibiotics) 5.1% (1 low-velocity
debride in OR as per 28 (penicillin/ fracture, no anti-
open-fractures protocol streptomycin) biotics; 3 shotgun
24 (cephalothin) wounds treated with/
without antibiotics)
Local wound care,
à
27 0%
immediate locked
femoral nailing
No specific wound protocol, 3 (time to OR <12 h) 0%
#
internal fixation according 34 (time to OR 12-72 h) 2.1%
#
to fracture 43 (time to OR >72 h) 4.6%
#
Local wound care,
à
39 2.5%
immediate locked
femoral nailing
Local wound care,

à
18 0%
immediate locked
femoral nailing
Local wound care with 118 (cephapirin/ 1.7% (cephapirin/
povidone in ED gentamicin) gentamicin)
100 (ciprofloxacin) 2.0% (ciprofloxacin)
tainty as to the type of weapon
used suggests the need for formal
surgical debridement.
13,37
Patients
presenting 8 or more hours after
injury may also benefit from opera-
tive debridement, as local wound
care is potentially less efficacious
by this time. Other surgical indi-
cations include unstable frac-
tures,
21,30,44,46,47
selected cases with
spinal involvement,
30,49
tendon in-
juries, superficial fragments in the
palm or sole, and injuries to the
bony pelvis.
An absolute indication for inter-
vention is the presence of metallic
fragments in a joint cavity. It

should also be considered in the
presence of any articular involve-
ment.
28
Arthrotomy is often neces-
sary for adequate debridement, but
in uncomplicated cases, arthros-
copy can provide both valuable
diagnostic information and defini-
tive treatment.
28
All foreign bodies
and loose fragments of bone and
cartilage must be removed, and the
synovial membrane must be tightly
closed. Closed suction drainage
will prevent hematoma formation,
which is undesirable in the pres-
ence of soft-tissue compromise and
bacterial contamination.
In contrast to sharp, penetrating
trauma, there is no consensus re-
garding the optimal timing for ex-
ploration and repair of peripheral
nerve damage associated with gun-
shot and shotgun trauma.
40,50
Ad-
vocates of delayed treatment cite
the presence of both contusion and

laceration in these injuries.
24,40
Widespread contusion by a high-
energy projectile may lead to epi-
neurial softening and subsequent
suture failure. It can be difficult, if
not impossible, to determine the
extent of the injury, leading to inad-
equate resection of scar tissue back
to a healthy stump.
40
Furthermore,
spontaneous recovery frequently oc-
curs.
44,50,51
Omer
51
reported a 70%
recovery rate for upper-extremity
peripheral-nerve gunshot injuries,
with most gains occurring over 3 to
6 months. In a study of sciatic and
peroneal nerve injuries after gun-
shot trauma, Brien et al
44
noted that
in 60% of cases the affected nerves
regained some degree of function.
Therefore, acute repair appears to
be rarely indicated for isolated gun-

shot nerve injuries.
Dissection through dense scar
tissue (particularly neuroma-in-
continuity) is extremely difficult,
and immediate or early exploration
and reconstruction may be prefer-
able. Deitch and Grimes
9
suggested
prompt operative nerve explora-
tion if a shotgun injury has resulted
in major neurologic deficits not
related to ischemia or compartment
syndrome, as well as consideration
of primary repair of transected
nerves. The presence of an associ-
ated injury requiring surgical treat-
ment, such as a vascular lesion or
fracture, is a relative indication for
early nerve reconstruction.
24,40,50,52
Pain might also improve with sur-
gical treatment, particularly if the
bullet is lodged in a neural ele-
ment.
40,50
When wound exploration is per-
formed, primary repair or grafting
of major nerve injuries should be
considered.

9,40,51,52
Early interven-
tion simplifies dissection; grafting
distances may be shorter before
nerve retraction occurs, and neurot-
ization can be performed immedi-
ately if the roots have been avulsed.
Provided the patient is in good
overall condition, these advantages
have prompted some to consider
reconstruction of even isolated
nerve transections within 1 week of
injury.
52
If proper facilities are not
available, neural structures should
be cleansed, tagged, and covered
with soft tissue but not debrided;
repair should be delayed for 2 or 4
weeks.
24,40
Lesions-in-continuity
should not be resected immedi-
ately.
24
Currently, most authors delay
exploration of a lesion-in-continuity
for up to 6 months to allow for reso-
lution of any neurapraxia.
24,40

How-
ever, the disadvantage of waiting
too long is motor end-plate degen-
eration, which will limit the poten-
tial for recovery. In the case of some
lesions, it can take as long as 18
months to reestablish distal connec-
tions, by which time irreversible
motor end-plate degeneration and
replacement of muscle by fibrosis
and/or fat have occurred.
40
There-
fore, early exploration at 2 to 4
months, utilizing intraoperative
electrodiagnostic monitoring with
sensory and motor-evoked poten-
tials, appears to be optimal.
24,40,51
Fracture Treatment
Fractures secondary to gunshot
wounds are typically treated ac-
cording to accepted protocols for
each area of injury.
19,21,26,30,39,41,44,46,47,49
In one study,
46
the femur was in-
volved in 49% of cases, one or both
forearm bones in 23%, the humerus

in 17%, and the tibia in 11%. Treat-
ment of low-velocity, low-energy
fractures is generally dictated by
the bone injuries, as these have
characteristics similar to those of
closed fractures. Surgical interven-
tion must be carefully considered,
as one can theoretically increase the
risk of infection through further
disruption of the soft tissues, due to
disruption of the local blood sup-
ply. Therefore, if a fracture can be
easily controlled, nonoperative
management is preferred (Fig. 1).
However, unstable fractures re-
quire appropriate surgical stabiliza-
tion (Fig. 6). Soft tissues assume a
more critical role in high-velocity
and shotgun fractures, which are
essentially open injuries.
10,13,34
In
these cases, external fixation is of-
ten the optimal treatment modality
(Fig. 7).
Molinari et al
46
observed no sig-
nificant differences in the rates of
infection or nonunion when they

Ballistics and Gunshot Wounds
Journal of the American Academy of Orthopaedic Surgeons
32
compared early and delayed treat-
ment of 121 low-velocity gunshot
fractures. However, there was a
considerable reduction in the length
of hospital stay for the early treat-
ment group (5 days vs 17 days),
resulting in a cost saving of almost
$10,000 per patient. In other stud-
ies,
21,44,47
early fixation compared
favorably with delayed fixation, as
it resulted in shortened hospitaliza-
tion, no increase in complication
rate, and earlier mobilization of the
extremity.
For uncontaminated low-energy
fractures requiring stabilization,
the use of an intravenous antibiotic,
such as cefazolin, begun prior to
surgery and continued for 24 to 48
hours, is generally preferred. How-
ever, some authors have suggested
a 72-hour time period and the addi-
tion of an aminoglycoside.
44
Lib-

eral bone grafting will improve
Craig S. Bartlett, MD, et al
Vol 8, No 1, January/February 2000
33
A B
Figure 6 A, Radiograph of the left elbow of a 23-year-old man with a Monteggia fracture after low-velocity gunshot trauma. Although
the entry hole measured less than 1 cm, most of the contained kinetic energy of the bullet was released on impact, causing greater than
expected comminution and an associated ulnar nerve injury. An arteriogram revealed no vascular damage. B, Lateral view obtained after
debridement and open reduction and internal fixation. An antibiotic cement spacer was used temporarily to replace contaminated and
devascularized bone. On the second postoperative day, signs of compartment syndrome necessitated fasciotomy. The ulnar nerve was
also explored, found to be completely disrupted, and its ends tagged for future grafting. When the condition of the tissues had improved,
the spacer was removed; a large tricortical iliac-crest bone graft was placed; and the fixation was supplemented.
A B C D
Figure 7 A, Lateral view of the left tibia and fibula of a 22-year-old man after a close-range shotgun wound to the left distal tibia. B, AP
view of the left tibia and fibula after debridement of devitalized contaminated bone and placement of an external fixator (old Wagner
type). At 1 week, the patient returned to the operating room for debridement and free tissue transfer. C, AP view of the left tibia and
fibula at 1 month. When the tissues appeared healthier, the patient underwent fibular stabilization, conversion to an AO-type fixator, and
iliac-crest bone grafting. Although bone grafting of large defects has been shown to be effective, distraction osteogenesis or vascularized
fibula transfer is now more often the treatment of choice for large defects. D, AP view of the left tibia and fibula at 3-year follow-up
shows complete healing. The functional result was good.
union rates for most high-velocity
injuries.
2
This is especially important
for shotgun-related fractures (Fig. 7),
for which anatomic reduction is
often impossible due to comminu-
tion and bone loss, with nonunion
rates reaching 63%.
2

Although
selective shortening, creation of a
synostosis, and segmental replace-
ment of long-bone defects after
gunshot wounds have been advo-
cated in the past,
53
modern princi-
ples of limb lengthening and vas-
cularized fibula transfer are also
applicable.
Treatment of High-Energy
Wounds
Although there are no immutable
rules, general principles of trauma
management applicable to all types
of gunshot trauma should be fol-
lowed. High-energy wounds man-
date immediate and aggressive irri-
gation and debridement, including a
thorough search for foreign material,
such as clothing fragments and shot-
gun wadding.
9
Open-fracture pro-
tocols including external fixation or
intramedullary nailing and intra-
venous antibiotics (a first-generation
cephalosporin with the possible
addition of an aminoglycoside,

penicillin, or a broad-spectrum
antibiotic) for at least 48 to 72 hours
should be instituted. If there is vas-
cular damage, exploration and re-
pair are best performed after prompt
fracture stabilization.
With few exceptions, wounds
will require enlargement by incision.
The margins of the entrance and exit
wounds should be excised, and the
track thoroughly irrigated. With or-
dinary high-velocity missile injuries,
this margin can be as small as 1 to 5
mm in width.
20
However, severely
damaged and devitalized flaps may
require substantial debridement,
necessitating skin grafting. If possi-
ble, the track is identified by passing
a length of saline-soaked gauze
through it.
22
All contaminated and
crushed subcutaneous fat should be
removed, ischemic or grossly conta-
minated (after cleansing) muscle
excised, and devitalized bone frag-
ments discarded (Figs. 6, B; 7, B).
Fascia, like skin, may require only

limited debridement, but, if perfo-
rated, must be incised to permit
exposure of more extensively dam-
aged underlying tissue. If there is
any question of elevated compart-
ment pressures, fasciotomy should
be performed. Elimination of dead
space is desirable, but primary clo-
sure of bullet wounds must be
avoided because of the possibility of
contamination.
The evaluation and treatment of
damaged muscle is one of the sur-
geonÕs greatest challenges. Inade-
quate debridement is unfortunately
often the rule rather than the ex-
ception,
13
as devitalization is not
always immediately appreciated.
Although the Òfour CsÓÑcolor,
consistency, contractility, and the
capacity to bleedÑcontinue to pro-
vide valuable information more
than 40 years after their descrip-
tion,
8
they remain controversial.
Color and the capacity to bleed can
be misinterpreted in the presence

of shock or a tourniquet, and con-
tractility can be attenuated by hy-
pothermia and some forms of anes-
thesia. The consistency of the tis-
sue can be an extremely reliable
indicator, but it is a vague concept
that is difficult to quantify and
therefore impossible to use as an
absolute criterion. Ultimately, it is
the surgeonÕs experience in inter-
preting these physical findings that
is the most important factor.
Muscle is generally well vascular-
ized; therefore, to prevent overzeal-
ous debridement, marginally viable
tissue may be temporarily pre-
served pending further evaluation
and debridement.
7,13
Blood vessels require debride-
ment after high-energy injuries.
13
If extensive intimal damage has
occurred, complete transection and
debridement of each vessel end are
necessary. Because of their extensi-
bility, vessels can often be debrided
and anastomosed. If this is not
possible, a reversed autogenous
saphenous vein graft is the best al-

ternative.
9,13,45,51
Depending on the status of the
patient and the wounds, second-
look procedures should be per-
formed repeatedly during the 2 to
10 days after the injury, with the
excision of any remaining marginal
tissue. If the wounds remain clean,
early closure may be performed.
9,22
The benefits of early wound clo-
sure include a shortened hospital
stay, fewer scar contractures and
stiff joints, and a reduced risk of bac-
terial colonization, which routinely
occurs in granulating wounds.
9
Closure is best achieved within the
first 10 days, as the skin edges are
usually still mobile and may be
easily approximated. Skin grafting
becomes preferable when tension is
required for closure. A variety of
other soft-tissue procedures, in-
cluding use of local rotation flaps
or free tissue transfer, may be
necessary, especially for shotgun
wounds, which also often require
neurovascular and osseous recon-

structive procedures or even ampu-
tation.
6,10,24
Summary
The unique characteristics of long
bones and their intimate relation-
ships with surrounding muscle and
neurovascular structures lead to a
variety of injury patterns. Therefore,
it is important to have a thorough
understanding of ballistics and the
pathophysiology of missile injuries.
Although bullets are not steril-
ized on discharge, most low-velocity
gunshot wounds can be safely treat-
ed nonoperatively with local wound
care and outpatient management.
Because contamination is not al-
Ballistics and Gunshot Wounds
Journal of the American Academy of Orthopaedic Surgeons
34
ways apparent, most authors still
recommend routine antibiotic pro-
phylaxis.
The treatment of low-velocity,
low-energy fractures is generally
dictated by the osseous injuries.
High-energy injuries and grossly
contaminated wounds mandate
aggressive irrigation and debride-

ment and the use of open fracture
protocols including external fixation
or intramedullary nailing and intra-
venous antibiotic therapy for 48 to
72 hours. If there is vascular dam-
age, exploration and repair are best
performed after prompt fracture
stabilization. Distal neurologic
deficit alone is not an indication for
exploration, as it often resolves
without surgical intervention.
Acknowledgments: The authors would
like to thank Edward C. Yang, MD,
Richard E. Stern, MD, Ely L. Steinberg,
MD, and Robert S. Rozbruch, MD, for their
contributions to the preparation of this
manuscript.
Craig S. Bartlett, MD, et al
Vol 8, No 1, January/February 2000
35
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Ballistics and Gunshot Wounds
Journal of the American Academy of Orthopaedic Surgeons
36